mariadb/mysql-test/suite/innodb/include/crc32.pl
Marko Mäkelä dd72d7d561 MDEV-18025: Improve test case and consistency checks
Write a test case that computes valid crc32 checksums for
an encrypted page, but zeroes out the payload area, so
that the checksum after decryption fails.

xb_fil_cur_read(): Validate the page number before trying
any checksum calculation or decrypting or decompression.
Also, skip zero-filled pages. For page_compressed pages,
ensure that the FIL_PAGE_TYPE was changed. Also, reject
FIL_PAGE_PAGE_COMPRESSED_ENCRYPTED if no decryption was attempted.
2018-12-19 15:45:35 +02:00

33 lines
721 B
Raku

# The following is Public Domain / Creative Commons CC0 from
# http://billauer.co.il/blog/2011/05/perl-crc32-crc-xs-module/
sub mycrc32 {
my ($input, $init_value, $polynomial) = @_;
$init_value = 0 unless (defined $init_value);
$polynomial = 0xedb88320 unless (defined $polynomial);
my @lookup_table;
for (my $i=0; $i<256; $i++) {
my $x = $i;
for (my $j=0; $j<8; $j++) {
if ($x & 1) {
$x = ($x >> 1) ^ $polynomial;
} else {
$x = $x >> 1;
}
}
push @lookup_table, $x;
}
my $crc = $init_value ^ 0xffffffff;
foreach my $x (unpack ('C*', $input)) {
$crc = (($crc >> 8) & 0xffffff) ^ $lookup_table[ ($crc ^ $x) & 0xff ];
}
$crc = $crc ^ 0xffffffff;
return $crc;
}